My last Cooking Tip was all about gelatin, the different forms and how to use it. Because gelatin is derived from animals, it is not suitable for vegetarians & vegans. This Cooking Tip will discuss vegetarian alternatives to gelatin.
Agar – Unlike gelatin, which is protein, agar is a carbohydrate made from raw seaweed. This makes it popular with vegetarians. It is commonly used in Asian cuisines. Although agar can be used in place of gelatin, there are different characteristics.
- Acidity – Gelatin does not set will in mixtures with a pH below 4. Agar will set up in much more acidic environments with a range of 2.5 to 10. This allows for gelling dishes such as those that are citrus-based. Normally, those would be too acidic for gelatin to work.
- Temperature – There is a much larger differential between proper setting temperature and melting temperature as compared to gelatin. It sets at about 95°F but doesn’t melt until 175°F. This allows one to serve a warm gel, something impossible with gelatin. This also makes a difference in mouthfeel. Gelatin tends to melt in your mouth as you eat it as it has a lower melting temperature. Agar’s higher melting temperature means it will have a firmer texture as you eat it.
- Setting time – Agar sets very rapidly once it reaches that 95°F, within minutes rather than hours for gelatin.
- Texture – Agar gels set very firm and can become brittle. This can be counteracted by the addition of sorbitol or glycerol in an amount of about 1% by weight.
- Appearance – A gel set with agar can look clear or opaque.
- Use Percentage – to use agar, you would use a percentage between 0.2% for a standard gel to 0.5% for a firm gel. If you recall the math lesson from the Gelatin Tip, this means using either 2 grams or 5 grams to set 1000 grams of liquid. Gelatin has a use percentage of between 0.6% & 1.7%. Therefore, you can see that agar will have a stronger set at the same amount, but more is not better with agar as the texture can become unpleasant.
One of the challenges with agar is that its strength can vary from brand to brand. Cooks Illustrated looked at this and found that ¾ teaspoon of the Eden brand thickened one cup of water just as 1 teaspoon of gelatin. They also found that it took more liquid and more time to dissolve. They caution that it will not, however, thicken cream or milk-based liquids.
- Hydration – Just as gelatin, agar needs to be hydrated before using. The recommended procedure is to whisk it into the liquid to dissolve it and then simmering for about 4 minutes. This is followed by blending it for 15-30 seconds with an immersion blender, straining it and then allowing it to set. The blender step ensures even dispersion and hydration. A regular blender is not recommended as it incorporates too much air into the mixture.
- Weeping – Agar gels can leak liquid and dehydrate making it less effective in gelling. One work-around for this is said to be adding 0.1% by weight of locust bean gum. Agar will also dehydrate if left uncovered.
- Tannic acid – An inhibitor of agar gels is tannic acid, a substance commonly found in red wine and tea.
- High alcohol content (about 40%) – Agar can work in this environment whereas gelatin does not.
- Fruit – Proteolytic enzymes inhibit gelatin but not so for agar. So, you can use it to make gels with fresh fruits that contain such enzymes.
Carrageenan – Another seaweed-derived product, this is more commonly used as a firming agent in vegan cheese. There are different types suited better to different uses.
Vegetable Gums – These are commonly found in ice creams, chewing gum and gluten-free baked goods. Examples include guar gum and xanthan gum. One brand name is Natural Desserts Unflavored Jel Dessert. This product was tested by Cooks Illustrated in panna cotta and a strawberry gelatin. They found it did work but it was much softer and they recommended using 1½ times of the amount of gelatin specified in the recipe. They also found it to be ineffective in acidic environments. I am not totally sure that this product is still available but there are other brands that would probably be comparable.
If you are wanting to make a switch from gelatin to a vegetarian/vegan substitute, I would start with agar. It has been used and evaluated more extensively than the other options.